Circuit device and method for manufacturing the same

ABSTRACT

In order to provide a circuit device  10  where a second circuit element  15 B is exposed froma sealing resin  16,  a circuit device  10 A comprises: an island  12  to whose top a first circuit element  15 A is fixedly fitted; a plurality of leads  11  which are extended around the island  12  and electrically connected to the first circuit element  15 A; a sealing resin  16  which seals the first circuit element  15 A, the island  12,  and leads  11  and forms a cavity portion  18;  and a second circuit element  15 B stored in the cavity portion  18.  Accordingly, since the second circuit element  15 B can be externally provided, the degree of freedom for mounting can be improved.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a circuit device having aplurality of circuit elements such as semiconductor devices and a methodfor manufacturing the same.

[0003] 2. Description of the Related Art

[0004]FIG. 8 is a plan view of a circuit device 100, and a structurethereof will be described with reference to the drawing.

[0005] In the vicinity of a central portion of the circuit device 100,an island 101 is arranged. A plurality of semiconductor elements 105 aresecurely fitted on the island formed in a rectangular form. A pluralityof leads 102 extend so as to surround the island 101. One end of thelead 102 is approximated to the island 101 and is electrically connectedto the semiconductor element 105 by a thin metal wire 103. In addition,the other end of the lead 102 extends outside from a sealing resin 104to seal the whole and forms an external electrode.

[0006] However, in the above-described circuit device 10, allsemiconductor elements 105 are sealed by the sealing resin 104. Inaddition, if either of the semiconductor devices 105 is a semiconductorelement having a memory, replacement of the semiconductor element isrequired for a change of this memory. Therefore, because allsemiconductor devices are resin-sealed, rearrangement of semiconductorelements is troublesome in the circuit device 10, therein a problem hasexisted.

[0007] Furthermore, since the plurality of semiconductor elements 105are built in, if a failure occurs in either semiconductor element 105,the circuit device 100 itself fails, and improvement in the yield islimited, therein a problem has existed.

SUMMARY OF THE INVENTION

[0008] The embodiment of present invention has been made in view of theproblems, and it is a principal object of the embodiment of presentinvention to provide a circuit device which solves the above-describedproblems by a structure wherein built-in circuit elements are exposedfrom a sealing resin.

[0009] A circuit device of the embodiment of present invention has aconfiguration in which circuit element is sealed by a sealing resin,wherein a cavity portion is provided in the sealing resin, and thecircuit element is stored in the cavity portion.

[0010] A circuit device of the embodiment of present inventioncomprises: an island on which a first circuit element is affixed; aplurality of leads which extend around the island and are electricallyconnected to the first circuit element; a sealing resin which seals thefirst circuit element, island, and leads and forms a cavity portion; anda second circuit element stored in the cavity portion.

[0011] A method for manufacturing a circuit device of the presentinvention comprises: sealing a first circuit element electricallyconnected to an external electrode with a sealing resin, andfurthermore, providing a cavity portion in the sealing resin; andstoring a second circuit element in the cavity portion.

[0012] According to the embodiment of present invention, the secondcircuit element 15B can be stored in the cavity portion 18 provided inthe sealing resin 16 to seal the whole. Accordingly, by only a change ofthe second circuit element 15B, functions of the circuit device 10 canbe changed.

[0013] Furthermore, if a semiconductor element having a memory portionsuch as a ROM is employed as a second circuit element 15B, it becomespossible to incorporate user-specific information into the secondcircuit element 15B. Accordingly, by commonly using the first circuitelement 15A of a signal processing element and specializing the secondcircuit element 15B in each user, it becomes possible to respond torespective users only by changing the second circuit element 15B.

DESCRIPTION OF THE DRAWINGS

[0014]FIG. 1A is a perspective view and FIG. 1B is a sectional viewshowing a circuit device of the embodiment of present invention.

[0015]FIG. 2 is a plan view showing a circuit device of the embodimentof present invention.

[0016]FIG. 3A is a sectional view, FIG. 3B is a sectional view, and FIG.3C is a sectional view showing a circuit device of the embodiment ofpresent invention.

[0017]FIG. 4 is a plan view showing a circuit device of the embodimentof present invention.

[0018]FIG. 5A is a plan view and FIG. 5B is a sectional view showing amethod for manufacturing a circuit device of the embodiment of presentinvention.

[0019]FIG. 6 is a sectional view showing a method for manufacturing acircuit device of the embodiment of present invention.

[0020]FIG. 7 is a sectional view showing a method for manufacturing acircuit device of the embodiment of present invention.

[0021]FIG. 8 is a plan view showing a related circuit device.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Referring to FIG. 1, a configuration of a circuit device 10A ofthe present embodiment will be described. FIG. 1A is a perspective viewof the circuit device 10A, and FIG. 1B is a sectional view thereof.

[0023] Referring to FIG. 1A and FIG. 1B, the circuit device 10A of anembodiment comprises: an island 12 to whose top a first circuit element15A is fixedly fitted; a plurality of leads which extend around theisland 12 and are electrically connected to the first circuit element15A; a sealing resin 16 which seals the first circuit element 15A,island 12, and leads 11 and forms a cavity portion 18; and a secondcircuit element 15B stored in the cavity portion. These respectivecomponents will be described in the following.

[0024] As the first circuit element 15A, a semiconductor device isherein employed, and this is fixedly fitted on the island 12 via anadhesive. And, the first circuit element 15A and leads 11 areelectrically connected via thin metal wires 17. Furthermore, bridges 13and the first circuit element 15A are connected via thin metal wires 17.In addition, as the first circuit element 15A, a semiconductor elementto perform signal processing can be employed. Concretely, a circuit toprocess a moving image displayed on a display of a television or thelike can be formed on the first circuit element 15A. In addition, acircuit to control a memory portion, etc., of the second circuit element15B may be formed on the first circuit element 15A. In addition, as thefirst circuit element 15A, in addition to a semiconductor element, apassive element such as a resistor or capacitor and an active elementsuch as a diode can be generally employed. Furthermore, it is alsosatisfactory that a plurality of elements out of these are employed as afirst circuit element 15A.

[0025] As the second circuit element 15B, a semiconductor element can beemployed. The second circuit element 15B is fixedly fitted with its facedown to the leads 11 and bridges 13 exposed inside the cavity portion 18via a brazing material such as a solder. Herein, as the second circuitelement 15B, a semiconductor element having a memory portion such as aROM (Read Only Memory) can be employed. Concretely, additionalinformation such as a number of channels, which is displayed in a mannersuperposed with an image on a display portion of a television or thelike, can be built in the above-described ROM. In addition, as thesecond circuit element, it is also possible to employ, in addition to abare IC chip, a resin package having a semiconductor element built-in.When a package such as a BGA (Ball Grid Array) is employed as a secondcircuit element 15B, this is fixedly fitted to connection terminals 14by surface mounting.

[0026] As a material of the sealing resin 16, a thermoplastic resin or athermosetting resin can be generally employed. Herein, the first circuitelement 15A, second circuit element 15B, island 12, leads 11, andbridges 13 are sealed by the sealing resin 16. In addition, in a regionwhere the second circuit element 15B is placed, the cavity portion 18,which is a region where the sealing resin 16 has been partially removed,is formed.

[0027] The cavity portion 18 is a region where the sealing resin 16 hasbeen partially removed, and is formed so that the size is slightlygreater than that of the second circuit element 15B to be storedtherein. In addition, from four sides of a lateral side portion of thecavity portion 18, end portions of the leads 11 and end portions of thebridges 13 are exposed to form connection terminals to the secondcircuit element 15B. Herein, it is also possible to provide a pluralityof cavity portions 18.

[0028] Next, referring to FIG. 2, a plane configuration of the circuitdevice 10A will be mainly described.

[0029] For the island 12, material thereof is selected in considerationof adhesive characteristics of the brazing material, bondingcharacteristics, and plating characteristics, and the material is formedof a metal mainly of Cu, a metal mainly of Al, or an alloy such asFe—Ni. In addition, on the top of the island 12, the first circuitelement 15A is mounted via an adhesive.

[0030] The leads 11 are formed of a material identical to that of theabove-described island 12, wherein one end of each is approximated tothe island 12 and is connected to a element and the other end is exposedoutside from the sealing resin 16 to form an external electrode. Herein,the leads 11 are lead out from two opposing sides of the sealing resin16 to forma DIP (Dual Inline Package). However, it is also possible toemploy packaging methods of other embodiments such as a QFP (Quad FlatPackage) and a QFN (Quad Flat Non-leaded Package).

[0031] The bridges 13 are arranged in a plural number between the firstcircuit element 15A and second circuit element 15B, and have a functionto electrically connect both circuit elements. In addition, theindividual bridges 13 are electrically independently provided. Herein,the first circuit element 15A is connected to one end of the bridge 13via a thin metal wire 17. Furthermore, via a brazing material such assolder, the second circuit element 15B is connected to the other end ofthe bridge 13.

[0032] Referring to FIGS. 3, configurations of circuit devices of otherembodiments will be described. FIG. 3A to FIG. 3B are sectional views ofthe respective embodiments. A plane configuration is basically the sameas that of the above-described circuit device 10.

[0033] Referring to FIG. 3A, a configuration of the circuit device 10Bwill be described. Herein, inside the cavity portion 18, the sealingresin is formed under the bridge and lead 11. Other aspects of theconfiguration are the same as those of the circuit device 10A.

[0034] Referring to FIG. 3B, a configuration of the circuit device 10Cwill be described. Herein, the island 12, bridge 13, and lead 11 areformed on the surface of a mounting substrate 19, and an externalelectrode 20 provided in a manner penetrating the mounting substrate 19and the lead 11, etc., are electrically connected.

[0035] Referring to FIG. 3(C), a configuration of the circuit device 10Dwill be described. Herein, the island 12, bridge 13, and lead 11 areformed in a manner embedded in the sealing resin 16. In addition, sidesurfaces of the lead 11, etc., are formed in a curved manner, wherebyadhesion to the sealing resin 16 is improved.

[0036] Next, referring to FIG. 4 to FIG. 7, a method for manufacturingthe circuit device 10A shown in FIG. 1 will be described.

[0037] First, referring to FIG. 4, an island 12, bridges 13, and leads11 are formed by shaping a metal plate. This step can be carried out bya press or etching step. Herein, suspension leads to fix the island 12may be provided. In addition, since the bridges 13 are not electricallyconnected to other positions, the bridges 13 can be fixed by taping thebridges 13 to an adhesive tape 21. In addition, connection terminalsformed of end portions of the bridges 13 or leads 11 are formed around acavity portion 18 to be formed.

[0038] Next, referring to FIG. 5, a first circuit element 15A is fixedlyfitted. First, via an adhesive, the first circuit element 15A is fixedlyfitted to the island 12. Next, via thin metal wires 17, the leads 11 orbridges 13 and the first circuit element 15A are electrically connected.

[0039] Next, referring to FIG. 6, the upper surfaces of connectionterminals 14 in a position where a second circuit element 15B isconnected are protected while sealing is carried out by a sealing resin16. This step can be carried out by injection molding by use of athermoplastic resin or transfer molding by use of a thermosetting resin.A metal mold used in this step is composed of an upper metal mold 22 anda lower metal mold 23, and a convex part 22A of a size corresponding tothe cavity portion 18 is provided in the upper metal mold 22.Furthermore, in the lower metal mold 23 as well, a convex part 22A maybe provided at an identical position to the upper metal mold.

[0040] Resin sealing is carried out in a condition where the lowersurface of the convex part 22A of the upper metal mold 22 is in contactwith the upper surface of the connection terminal 14. Thereby, thesealing resin 16 is prevented from adhering to the upper surfaces of theconnection terminals 14. Furthermore, resin sealing may be carried outafter the upper surfaces of the connection terminals 14 are covered by aresinous tape. In addition, after this step ends, quality of the firstcircuit element 15A and connection positions thereof is checked bymeasurement of electrical characteristics. And, only ones judged to benon-defective by this measurement are transferred to the next step.Accordingly, since only confirming second circuit elements 15B areemployed in the next step as well, the yield can be improved.

[0041] Next, referring to FIG. 7, the second circuit element 15B isstored in the cavity portion 18. Concretely, the second circuit element15B is fixedly fitted with its face down to the connection terminals 14exposed inside from the four sides of the cavity portion 18 via abrazing material. Through the above steps, a circuit device 10A ismanufactured.

[0042] In addition, in the present embodiment, the circuit device 10Acan also be delivered, without fixedly fitting the second circuitelement 15B by a brazing material, only with the second circuit element15B mechanically stored in the cavity portion 18. In this case, althoughthe second circuit element 15B is not fixedly fitted, since the secondcircuit element 15B is mechanically in contact with the contactterminals 14, a test can be performed without a problem. Fixed fittingof the second circuit element 15B can be simultaneously performed in areflow step of placing the circuit device 10A on a motherboard or thelike. Accordingly, it becomes possible to change the second circuitelement 15B until the last step where the circuit device 10A is mountedon a set.

[0043] The advantage of present embodiment exists in that cavity portion18 is provided in the circuit device 10, and the second circuit element15B can be externally provided in this cavity portion 18. Concretely,the first circuit element 15A, which is a semiconductor element toperform signal processing, is built in the sealing resin 13. And, thesecond circuit element 15B having a memory portion where settinginformation, etc., is stored can be externally provided in theabove-described cavity portion 18. Accordingly, even when settinginformation is different depending on the users, by only preparing thesecond circuit element 15B for each user, other parts can be prepared incommon. For example, in terms of a control module of a video apparatussuch as a television, the character style and font size for displayingchannel numbers are different among users. Therefore, by storing theinformation in the second circuit element 15B, a circuit device 10 as acontrol module to satisfy user demands can be provided by only replacingthe second circuit element 15B.

What is claimed is:
 1. A circuit device in which circuit element issealed by a sealing resin, wherein a cavity portion is provided in thesealing resin, and the circuit element is stored in the cavity portion.2. The device of claim 1, wherein the circuit element comprises a firstcircuit element sealed by the sealing resin and a second circuit elementstored in the cavity portion, and the first circuit element and thesecond circuit element are electrically connected.
 3. The device ofclaim 1, wherein connection terminals are provided in a peripheralportion of the cavity portion, and the circuit element is electricallyconnected to the connection terminals.
 4. The device of claim 2, whereinthe first circuit element is a semiconductor element to perform signalprocessing, and the second circuit element is a semiconductor elementhaving a memory portion controlled by the first circuit element.
 5. Acircuit device comprising: an island on which a first circuit element isaffixed; a plurality of leads which extend around the island and areelectrically connected to the first circuit element; a sealing resinwhich seals the first circuit element, island, and leads and forms acavity portion; and a second circuit element stored in the cavityportion.
 6. The device of claim 5, wherein between the first circuitelement and second circuit element, bridges for electrically connectingboth circuit elements are provided.
 7. The device of claim 6, whereinend portions of the leads and bridges are exposed in a peripheralportion of the cavity portion, and the second circuit element is mountedon the end portions.
 8. The device of claim 5, wherein the first circuitelement is a semiconductor element to perform signal processing, and thesecond circuit element is a semiconductor element having a memoryportion controlled by the first circuit element.
 9. A method formanufacturing a circuit device comprising: sealing a first circuitelement electrically connected to an external electrode with a sealingresin, and furthermore, providing a cavity portion in the sealing resin;and storing a second circuit element in the cavity portion.
 10. Themethod of claim 9, wherein after performing a test of the first circuitelement, the second circuit element is stored.
 11. The method of claim9, wherein the second circuit element is placed on connection terminalsprovided in the cavity portion, and in a step of mounting the circuitdevice by a reflow, fixed fitting of the second circuit is performed.